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MarcEisenmann - 11:24, Wednesday 05 July 2023 (3283)Get code to link to this report
Polarizers and LC calibration

In order to characterize the polarization states generated by our LCs, we can rotate the output polarizer while applying different voltages to our LC.

As our motorized rotator is from Thorlabs, we had to switch the position of our input and output polarizers.

We estimated the extinction ratio of our polarizers to be about 25 000 each.

Then, we calibrated again each LCs as shown in fig 1 and 2 for LC1 and 3 and 4 for LC2.

Their respective fast axis direction is 45.74 deg and 69.00 deg.

From figures 2 and 4, the maximum retardation at these angles is below 6 nm offset from 532 nm which indicates a misalignment of about 0.01 deg from the fast axis from simulation.

Images attached to this report
3283_20230705042427_lc1fastaxis.png 3283_20230705042430_lc1retardation.png 3283_20230705042433_lc2fastaxis.png 3283_20230705042436_lc2retardation.png